Quite good introduction to modern official way of building DEB packages. Only a little more work than with FPM, but the results are much, much better, and package build procedure is not something totally external to the package itself (FPM has exactly that problem: where to put tools invocations?).

This is not really an "official" way of building packages. There are many things that wouldn't be allowed if the package were to be uploaded to Debian. But since the same tools than for regular packages are used, you can also iteratively "enhance" the package to be more policy-compliant.